This invention relates to a crop harvesting header of the type comprising a frame for mounting on a crop harvesting machine for movement across ground carrying a crop to be harvested, the frame defining a working width of the header, a table mounted on the frame across the width of the header for receiving the crop when cut for transportation along the header, a cutting knife along a front edge of the table for cutting the crop and a pickup reel comprising a main elongate support beam, a plurality of bats at angularly spaced positions around the main beam, a pair of support arms carried on the frame and extending forwardly therefrom for supporting the beam at a forward end of the arms and means for adjusting the position of the main longitudinal axis of the beam and relative to the cutter knife for different crop conditions.
A reel of this type is shown in U.S. Pat. Nos. 5,768,870-4,776,155 and 4,751,809 all of which are assigned to the present assignee.
The second of the above patents is particularly directed to the bat angle adjustment system which controls the angle of the bats as they rotate about the main longitudinal axis of the beam so as to maintain an angle of the bats relative to a vertical plane through the bat substantially constant as the bats move through the region adjacent the cutting knife. This bat control system includes an eccentrically mounted control disc which is shaped and arranged to provide the necessary advancement and retardation of the fingers of the bat as the bat rotates about the main longitudinal axis of the beam.
The first of the above patents shows that it is well known that the reel is adjustable so as to vary the height of the reel by pivoting the support arms about their point of connection to the frame. Furthermore the position of the reel along the length of the support arms is adjustable so as to move the reel and particularly the bats forwardly and rearwardly relative to the cutting knife for different crop conditions. Yet further, it is also possible to adjust the angle of the fingers, relative to a vertical plane passing through each bat axis, which is maintained constant as the bat passes through an arc adjacent the knife.
The slope of the main part of the reel support arm is arranged generally parallel to the slope of the table and draper from the knife so that the height of the reel above the cutter bar and draper is controlled by the slope during the fore and aft movement in order that the reel does not contact the knife and cutter-bar or the draper conveyor as the reel is moved fore aft.
However, when cutting with the knife off the ground (for example rice) it is desirable to move the reel forward of the knife and downwardly in front of the knife to pick up the rice and leave as much of the wet stem on the ground as possible.
To the contrary, when cutting with the knife on the ground (soybeans) the reel is moved forward to pick up down plants ahead of the cutter-bar. It is then necessary to raise the reel to prevent the reel from contacting the ground and possibly damaging the reel or breaking fingers.
These two controls of the fore and aft movement and the height of the reel are independently operable by the operator who then has the responsibility of ensuring that the reel takes up the required position for the most efficient harvesting of the crops concerned.
It is one object of the present invention to provide an improved header which allows the position of the reel on the header relative to the knife to be adjusted more effectively.
According to one aspect of the invention there is provided a crop harvesting header comprising:
a frame for mounting on a crop harvesting machine for movement across ground carrying a crop to be harvested, the frame defining a working width of the header;
a table mounted on the frame across the width of the header for receiving the crop when cut for transportation along the header;
a cutting knife along a front edge of the table for cutting the crop;
and a pickup reel comprising:
a main elongate beam extending along the header generally parallel to the cutting knife;
at least two reel support arms spaced along the width of the frame, each having a rear end mounted on the frame for vertical pivotal movement providing adjustment for raising and lowering the reel relative to the cutting knife and a forward end for supporting the main elongate beam;
means mounting the main beam for rotation about a main longitudinal axis thereof;
a plurality of elongate bats;
means mounting the bats at angularly spaced positions around the main elongate beam for rotation therewith;
beam support members mounting the main elongate beam on the support arms for sliding adjustment movement forwardly and rearwardly on the support arms so as to adjust the horizontal position of the beam relative to the cutting knife;
and a linkage responsive to the forward sliding movement of the main elongate beam along the support arms for simultaneously and automatically causing a raising movement of the reel support arms.
Preferably the linkage is arranged to effect the raising movement only over a forward part of the sliding movement beyond a predetermined position and not over a part of the sliding movement rearward of the predetermined position. In this way the reel follows the slope of the arms behind the predetermined position so as to follow the slope of the table down to the knife and in front of the knife the arms are raised as the reel moves forwardly.
Preferably the linkage is arranged to be readily dis-engageable and re-engageable such that, when disengaged the reel support arms are not raised as the beam undergoes the forward sliding movement. In this way, the reel can continue to follow the slope of the arms downwardly and forwardly as it moves in front of the knife for use in crop where the knife is raised and the bats need to move downwardly to a position in front of and below the height of the knife.
Preferably the linkage is arranged relative to the forward and downward slope of the arms such that the beam moves in the forward part substantially horizontally so as to follow the ground.
Preferably the arms are straight so as to define a constant slope forwardly and downwardly since this avoids undesirable changes in finger angle of the bats as explained in the above prior patent.
Preferably each arm is lifted by an actuator having a first end connected to the frame and a second end connected to the arm and wherein the linkage includes a member connected between one of the first and second ends and the respective one of the frame and the arm so as to increase the effective length of the actuator. This is one simple way to effect the movement but it will be appreciated that many alternative arrangements can be designed to fulfil this function. Other mechanical linkages could be provided or even hydraulic coupling arrangements could be used to effect the function of automatically raising the arms as the beam moves forward beyond the predetermined location which is aligned with the knife.
In the above example, the member connected between one of the first and second ends and the respective one of the frame and the arm is a bell crank.
Preferably the linkage includes a cable which is slack rearward of the predetermined position and becomes tensioned at the predetermined position.
According to a second more limited definition of the invention there is provided a crop harvesting header comprising:
a frame for mounting on a crop harvesting machine for movement across ground carrying a crop to be harvested, the frame defining a working width of the header;
a table mounted on the frame across the width of the header for receiving the crop when cut for transportation along the header;
a cutting knife along a front edge of the table for cutting the crop;
and a pickup reel comprising:
a main elongate beam extending along the header generally parallel to the cutting knife;
at least two reel support arms spaced along the width of the frame, each having a rear end mounted on the frame for vertical pivotal movement providing adjustment for raising and lowering the reel relative to the cutting knife and a forward end for supporting the main elongate beam;
means mounting the main beam for rotation about a main longitudinal axis thereof;
a plurality of elongate bats;
means mounting the bats at angularly spaced positions around the main elongate beam for rotation therewith;
beam support members mounting the main elongate beam on the support arms for sliding adjustment movement forwardly and rearwardly on the support arms so as to adjust the horizontal position of the beam relative to the cutting knife;
the support arms having a forward and downward slope such that the beam moves downwardly as it slides forwardly;
and a linkage responsive to the forward and downward sliding movement of the main elongate beam along the support arms for simultaneously and automatically causing a raising movement of the reel support arms only over a forward part of the sliding movement beyond a predetermined position;
the linkage being arranged not to effect the raising movement over a part of the sliding movement rearward of the predetermined position;
the linkage being arranged relative to a forward and downward slope of the arms such that, over the forward part of the movement, the beam moves substantially horizontally;
the linkage being arranged to be readily dis-engageable and re-engageable such that, when disengaged the reel support arms are not raised as the beam undergoes the forward sliding movement.